Sometimes, when looking inside the breeding caves at “Costa de las Focas” reserve, technicians see incredible behaviors, like, if even rare to see, two pups feeding on milk  from the same female.

 

Observing this type of behavior, you may get the conclusion that those two pups are related but after watching for a few more minutes you find out that what you thought was happening is quite far from truth: those pups are not twins; the female is not the mother of both; that female is not aware of what is happening; and most of the times she is not tolerating this type of behavior at all.

Well, if what said above is true, how do we get to that double lactation?

What usually happens is that the alien pup is close enough to the pair mother-pup while the pup is feeding and just takes advantage of the situation. And this could happen because when nursing the female is on its side and sleeping, so the alien pup gets the chance of getting some free milk, and it does… until the female finds out that another pup than hers is feeding on milk from her, and she pushes away the alien pup with very bad manners!